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The case of the sizzling power bar…

For the past week or so, the power bar that sits on the edge of my desk has been making some crackling noises. I thought it was the one adapter plugged into it with some restless capacitors. As days went on, the noises were getting louder and today I got a whiff of something burning. Of course, I had to pull the plug… and explore.Opening it was not difficult; Just six screws to pop. The yellow wrapper around the surge protection circuit was harder to get off.As I popped the circuit and the power rails out of the plastic casing, one rail immediately fell off. I thought it was fine because I figured it was the plastic casing holding it all together, and I guess that what they thought too. It’s actually soldered as the other rails stayed on.I suspect this loose connection is what all the crackling was from.The surge protection circuit consists of three MOVs, or metal-oxide varistors, and a thermal cutoff fuse. The MOVs basically act as an overflow valve: Too much voltage and it conducts to send the extra to ground. I’ll be salvaging the power cord, toggle switch, and thermal fuse. I’ll keep the MOVs too if the legs are still a decent length.

So that was pretty fun. Except the part about how I’m out of a power bar.